package com.hisense.proxy.service.utils;


import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.util.HashMap;
import java.util.Map;

import javax.imageio.ImageIO;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.Writer;
import com.google.zxing.WriterException;
import com.google.zxing.client.j2se.MatrixToImageWriter;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
import com.google.zxing.qrcode.encoder.ByteMatrix;
import com.google.zxing.qrcode.encoder.Encoder;
import com.google.zxing.qrcode.encoder.QRCode;

/**
 * Author:wz
 */
public class QrcodeUtil implements Writer {
    private static final int QUIET_ZONE_SIZE = 4;
    private static String s = "www.zkong.com";

    public static void main(String[] args) throws Exception {
        new QrcodeUtil().createQRCode(s, 120, 120);
    }

    /**
     * Éú³É¶þÎ¬Âë·½·¨
     *
     * @param content
     * @param width
     * @param height
     * @return
     * @throws Exception
     */
    public byte[] createQRCode(String content, int width, int height) throws Exception {
        HashMap<EncodeHintType, Comparable> hints = new HashMap<EncodeHintType, Comparable>();
        hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.M);
        hints.put(EncodeHintType.MARGIN, 2);

        BitMatrix bitMatrix = encode(content, BarcodeFormat.QR_CODE, width, height, hints);
        BufferedImage bufferedImage = MatrixToImageWriter.toBufferedImage(bitMatrix);
        ByteArrayOutputStream bos = new ByteArrayOutputStream();

        ImageIO.write(bufferedImage, "png", bos);
        byte[] imageBytes = bos.toByteArray();
        return imageBytes;
    }


    @Override
    public BitMatrix encode(String contents, BarcodeFormat format, int width, int height)
            throws WriterException {

        return encode(contents, format, width, height, null);
    }

    @Override
    public BitMatrix encode(String contents,
                            BarcodeFormat format,
                            int width,
                            int height,
                            Map<EncodeHintType, ?> hints) throws WriterException {

        if (contents.isEmpty()) {
            throw new IllegalArgumentException("Found empty contents");
        }

        if (format != BarcodeFormat.QR_CODE) {
            throw new IllegalArgumentException("Can only encode QR_CODE, but got " + format);
        }

        if (width < 0 || height < 0) {
            throw new IllegalArgumentException("Requested dimensions are too small: " + width + 'x' +
                    height);
        }

        ErrorCorrectionLevel errorCorrectionLevel = ErrorCorrectionLevel.L;
        int quietZone = QUIET_ZONE_SIZE;
        if (hints != null) {
            if (hints.containsKey(EncodeHintType.ERROR_CORRECTION)) {
                errorCorrectionLevel = ErrorCorrectionLevel.valueOf(hints.get(EncodeHintType.ERROR_CORRECTION).toString());
            }
            if (hints.containsKey(EncodeHintType.MARGIN)) {
                quietZone = Integer.parseInt(hints.get(EncodeHintType.MARGIN).toString());
            }
        }

        QRCode code = Encoder.encode(contents, errorCorrectionLevel, hints);
        return renderResult(code, width, height, quietZone);
    }


    // Note that the input matrix uses 0 == white, 1 == black, while the output matrix uses
    // 0 == black, 255 == white (i.e. an 8 bit greyscale bitmap).
    private static BitMatrix renderResult(QRCode code, int width, int height, int quietZone) {
        ByteMatrix input = code.getMatrix();
        if (input == null) {
            throw new IllegalStateException();
        }
        int inputWidth = input.getWidth();
        int inputHeight = input.getHeight();

        int outputWidth = width % inputWidth == 0 ? width : (width / inputWidth + 1) * inputWidth;
        int outputHeight = height % inputHeight == 0 ? height : (height / inputHeight + 1) * inputHeight;

        int multiple = Math.min(outputWidth / inputWidth, outputHeight / inputHeight);
        // Padding includes both the quiet zone and the extra white pixels to accommodate the requested
        // dimensions. For example, if input is 25x25 the QR will be 33x33 including the quiet zone.
        // If the requested size is 200x160, the multiple will be 4, for a QR of 132x132. These will
        // handle all the padding from 100x100 (the actual QR) up to 200x160.
//        int leftPadding = (outputWidth - (inputWidth * multiple)) / 2;
//        int topPadding = (outputHeight - (inputHeight * multiple)) / 2;
        int leftPadding = quietZone;
        int topPadding = quietZone;
        BitMatrix output = new BitMatrix(outputWidth + quietZone * 2, outputHeight + quietZone * 2);

        for (int inputY = 0, outputY = topPadding; inputY < inputHeight; inputY++, outputY += multiple) {
            // Write the contents of this row of the barcode
            for (int inputX = 0, outputX = leftPadding; inputX < inputWidth; inputX++, outputX += multiple) {
                if (input.get(inputX, inputY) == 1) {
                    output.setRegion(outputX, outputY, multiple, multiple);
                }
            }
        }

        return output;
    }
}